Rollers for feeding a continuous strand



Aug. 16, 1955 w. R. STEITZ 2,715,299

ROLLERS FOR FEEDING A CONTINUOUS STRAND Filed Aug. 14, 1952 INVENTOR. WILLIAM R-STEITZ United States Patent ROLLERS FoR FEEDING A CONTINUOUS STRAND William R. Steitz, Anderson, S. C., assignor to Owens- Corning Fiherglas Corporation, a corporation of Delaware Application August 14, 1952, Serial No. 304,353

Claims. (CI. 4917) This invention relates to the art of feeding continuous strands of material, and in particular to improvements in high speed coacting pulling rollers which are driven to produce linear speeds of their peripheries, for example, as high as 10,000 feet per minute.

In feeding a continuous strand of small diameter at such a high linear rate, the feeding rollers must rotate so rapidly that many problems immediately are created due to the inertia of the rollers, the necessity for enough friction between their contacting peripheries to firmly grasp the strand and the fact that at such high speeds centrifugal force literally expands the diameters of the pulling rollers, so that this additional factor must be provided for.

Pulling rollers having peripheral tires fabricated from tough resilient materials such as reinforced synthetic rubber or synthetic resins have been suggested as con structions which reduce the weight of the rollers, thereby to lessen their inertia and their tendency to expand and to provide for surfaces having appropriate coefiicients of friction with the material from which the continuous strand is fabricated. However, particularly where the strand being linearly fed is fabricated from a hard, smooth surface material, such as the numerous synthetic fibers or glass, considerable pressure between the peripheries of the two coacting rollers must be maintained in order to hold the strand firmly enough to feed it with sufiicient force to overcome resistance created by coating or forming elements of the overall apparatus. Where this considerable pressure exists between the peripheries of the rollers, excessive wear is likely to occur in random places on the tires or rims which may create excessive heat and which may even break the strand being fed. When such worn spots are encountered, it is necessary to replace the entire rim or tire in these suggested constructions.

The behavior of these linearly fed strands is dificult to predict and to control. Frequently, for no apparent reason, the strand may lick around one of the rollers and be wound on that roller before an operator can take any steps to prevent this from happening. When a strand is being linearly fed at such a high speed, it has been discovered that the strand must be kept under tension or the resistance of the air to its passage therethrough will cause the strand to pile up upon itself, as it were, introducing generally wave form patterns which also may cause the strand to become entangled either with itself or with portions of the apparatus. Attempts have been made to take advantage of this latter characteristic and to deliberately encourage the strand to assume wave form patterns to facilitate its control. However, for the most part the wave form patterns assumed by the strand, even when encouraged, are likely to be random and unpredictable.

The principal object of this invention, therefore, is to provide a pulling roller which has a strand contacting body made up of individually replaceable elements so that when worn spots occur only the worn portion of the strand contacting section of the wheel need be replaced.

It is a further object of this invention to provide a strand pulling roller so designed as to facilitate its cooperation with another in a pair of such rollers to provide for more secure grasping of the strand being pulled, to provide for better transferral of power from the one roller to the other and to encourage the strand being fed to assume more nearly controllable Wave form patterns, thereby facilitating its subsequent handling and packaging.

It is yet another object of this invention to provide a pulling roller having individually removable and replaceable lugs or ribs with their axes extending generally parallel to the axes of the rollers and protruding beyond the general periphery of the pulling rollers, whereby the lugs on each pulling roller tend to intermesh with the lugs on the other pulling roller of a cooperating pair, thereby to transfer power from the one roller to the other to move the strand through an indirect path between the rollers and to provide for grasping the strand over a substantial length of the strand rather than merely the line contact between the surfaces of the rollers at their point of tangency.

These and more specific objects and advantages, both operative and constructural, will be more apparent from the specification which follows and from the drawings, in which:

Fig. l is a somewhat diagrammatic view in elevation of apparatus designed for the purpose of forming a continuous strand of glass fibers and including pulling rollers embodying the invention.

Fig. 2 is a greatly enlarged fragmentary view in elevation of a pair of pulling rollers embodying the invention and illustrating how a strand is grasped and fed between their peripheries.

Fig. 3 is a vertical sectional view taken substantially on the line 3-3 of Fig. 2.

Fig. 4 is a still further enlarged view in side elevation of an individual replaceable lug with which pulling rollers embodying the invention are provided.

Fig. 5 is a vertical sectional view taken substantially on the line 5-5 of Fig. 4.

Fig. 6 is a view taken generally from the position indicated by the line 66 of Fig. 3 but shown on an enlarged scale and illustrating the manner of insertion of a lug into the rim of a pulling roller embodying the invention.

While pulling rollers embodying the invention have utility in any part or field where it is necessary to linearly feed a continuous strand of light weight, small diameter, and yet preferably having considerable tensile strength, for purposes of illustration their use will be described in connection with the formation and feeding of glass fiber strands.

A glass fiber stand, for example, the strand 1G in Fig. 1, comprises a substantial number of individual glass fibers 11 each of which may be only a few microns in diameter and there may he, say, 200 or more individual fibers 11 in a strand 10. Each of the fibers 11 may be formed by allowing a fine stream of molten glass to flow from a heated pool, for instance contained in the bushing 12. The formation of the fiber results from the glass flowing through one of a plurality of minute orifices 13 on the lower side of the bushing 12.

After the glass has started to fiow through one of the orifices 13, it is mechanically grasped and pulled at a high rate of speed selected to result in the glass stream being attenuated to the desired finished diameter of the individual fiber. This grasping and pulling is performed by pulling rollers, for example the pulling rollers generally indicated at 14 in Fig. l. The strand 10 is,

Patented Aug. 16, 1955 formed by gathering the individual fibers 11 together as by means of a gathering eye 15, and then leading the strand between the peripheries of the pulling rollers 14 which, as mentioned above, may be rotated 16 although, of course, such occurrence would be rare in any of the arts involved. Since the particular type of packaging or transporting means into which the strand is projected does not constitute any part of the instant invention, no specific disclosure of such use is made.

A pulling roller 14 embodying the invention consists of a hub 17 (Figs. 2 and 3) by means of which the roller 14 is mounted upon its shaft 18, a generally radial extending web 19 and a generally cylindrical rim portion 20. In the rollers shown in the drawings, the web 19 and rim 20 are illustrated as being unitarily molded from a synthetic resin. This construction has been suggested as providing a light weight structure having suflicient strength to withstand the high speeds and great forces involved and also as allowing for suflicient flexure of the rim 20 to permit clearance to be maintained between pulling roller peripheries when they are stationary and yet to have them contact each other when rotating at high speed.

Each of the rims 20 of the pulling rollers 14 embodying the invention has a plurality of axially extending openings 21 (see particularly Fig. 6) which may be formed as axial slots but which preferably should be rectangular and should not open to either edge of the rim 20. The slots 21 are equidistantly spaced around the circumference of a roller 14 and in each of them is located a strand driving lug 22 .(see particularly Figs. 4, 5 and 6) which actually contacts and drives the strand 10. V

In the embodiment of the invention disclosed in the drawings, each of the lugs 22 has a generally rectangular body 23, a generally flat base 24 larger in size than the body 23 and protruding both longitudinally and transversely beyond the body 23 to form an edge 25. Each of the lugs 22 also has a cap 26 illustrated as being a cylindrical segment and, like the base 24, extending both longitudinally and transversely beyond the body 23 to form a lip 27 opposed to and spaced from the lip 25'. The spacing between the lips 25 and 27 corresponds to the height of the body 23 therebetween and is also substantially equal to the radial thickness of the rim 20.

The lugs 22 must be fabricated from material having some elasticity so that they can be deformed enough to be inserted into the openings 21 if the openings are rectangular as shown in the drawings or, if they are slots which extend to an edge of the rim 20, the lugs may be formed of material having less elasticity and the lugs can merely be slid axially into place. Under these circumstances, the lateral dimensions of the body 23 probably should be slightl greater than the circumferential dimension of the slot openings 21 to bind the lugs in place.

As can best be seen by referring to Fig. 6, in the preferred form of the invention the openings 21, as mentioned, are rectangular. Therefore, in order to insert a lug 22 in place it is positioned inside the rim 20 and angled upwardly with its lip 25 against the interior of the rim 20 and its lip 27 extending through the opening 21 and exteriorly of the rim 20. The lug is inserted by first engaging its lips 25 and 27 with one edge of an opening 21 and then applying pressure in the direction of the arrow in Fig. 6 todeform one edge of the cap 26 enough to allow the lug to be forced radially of the pulling roller 14 into place. Since the centrifugal force acting on the lugs during rotation of the pulling rollers 14 is great, the lugs will be held outwardly in position during use.

In Fig. 2 is will be observed that the lugs 22 on, for example, the right hand pulling roller 14 are intermeshed with the lugs 22 on the left hand pulling roller 14. This is a natural result of the spaced caps 26 of the lugs 22 and the fact that only one of the pulling rollers 14 need be driven. It will be seen in Fig. 2 that when the lugs 22 intermesh, the strand 10 fed therebetween is deformed, being squeezed between a cap 26 on a lug 22, for example on the right hand pulling roller 14, and the outer surface of the rim 20 on the left hand pulling roller 14 between two adjacent lugs 22 on that roller. This results in contact with the strand over substantially all of the circumferentially extending surface of each lug 22, and it also deforms the strand 10 in a sinusoidal pattern as it is fed between the pulling rollers 14. The establishment of this minute, high-frequency wave form starts the strand in a wave form pattern which increases in amplitude and decreases in frequency as the strand passes through the air enrouterto packaging or further handling equipment located in its line of travel.

By thus firmly grasping the strand between the pulling I roller surfaces, better control over and uniformity in its rate of feeding result. By initiating a wave pattern of fixed dimensions, a better control over the general wave form pattern in which the strand falls is experienced. The individually replaceable lugs 22 thus improve the strand handling characteristics of pulling rollers embodying the invention as well as simplify the replacement of worn parts, and the design and construction of the pulling rollers themselves, and reduce the weightof the pulling rollers by eliminating structural members designed to retain the strand contacting portions of the rims in place on the rollers.

I claim: 1. Pulling rollers for linearly feeding a continuou strand between the contacting peripheries thereof, said rollers being mounted on spaced parallel axes and having generally circular rims, the rims of said rollers being spaced, and a plurality of individual elements removably mounted in the rims of said rollers and each protruding radial beyond the rim of one of said rollers a distance sufiicient to extend between such elements on the other of said rollers and into contact with such elements and the rim of said roller between such elements.

2. Apparatus for feeding a strand comprising-a pair of cooperating pulling rollers adapted to engage opposite sides of said strand, said rollers having cylindrical rims, there being a series of circumferentially spaced openings in the rims of each of said rollers, a plurality of rim elements of deformable resilient material, each of said elements having a cylindrical cap extending radially therebeyond, a body extending through an opening in said rim and an enlarged portion located interiorly of and against said rim for preventing movement of said element bodily in a radially outward direction, said rollers being mounted on parallel axes so spaced and said elements being of such size and so spaced circumferentially on said rollers that, at least during high speed rotation, each of said elements on each of said rollers extends between two of said elements on the other of said rollers,

, and into contact with the rim of said other roller, and

means for rotating said rollers at high speed.

3. Apparatus according to claim 2 in which the openings in said rims are rectangular and each of the caps on said elements is of lateral dimensions larger than the dimensions of the openings.

4. Apparatus according to claim 2 in which the caps on said elements are cylindrical and the axes of such cylinders are parallel to the axes of said rollers 5. Apparatus according to claim 4 in which the axes of said rollers are'so spaced that each of said caps contacts portions of two adjacent caps and the rim of the associated roller when said rollers are rotated at high speed.

References Cited in the file of this patent UNITED STATES PATENTS Brown June 6, 1939 

